Dental articulator.



P. 'A. KENNEDY.

DENTAL ARTIGULATOR. v APPLIOATION FILED JULY 7, 1910.

Patented Jan. 10, 1911.

- PATRICK ALFR D KENNEDY, or

REDFERN, NEAR SYDNEY, NEW SOUTH WALES,

AUSTRALIA.

DENTAL ,ARTICULATQR.

Specification of Letters Patent.

Patented Jan. 10, 1911.

Application filed. July 7, 1910. Serial No. 570,809.

To all whom it may concern:

Be it known that I, PATRICK ALFRED KEN- NEDY, a subject of the King ofGreat Brit-' ain and Ireland, residing at 16 Castlereagh street,Redtern, near Sydney, in'the State of New South Vales, Australia, haveinvented certain new and useful Improvements in Dental Articulators, ofwhich the following is a specification.

My invention relates to apparatus for carrying molds for artificialdentures in proper articulated relation during the making of thedentures.

,According to my invention the plaster molds are clamped to thearticulator pans by attachments which permit of ready adjustment in anydirection. The form of articulatm' in which this adjustment is etfectedincludes certain other improvements in connection with the hinge, whichis made with a ball joint fitting by which manipulation of the moldswhile clamped in the pans is facilitated.

Figure 1 is a perspective view of a dental articulator according to thepresent invention, and Fig. 2 an enlarged fragment section through thearticulator ball joint hinge.

A. is the back plate having at the bottom two tubular carriers B withpinching screws 7). Through these tubular carriers the rods C, whichcarry the lower pan D slide telescopically. "The pan D is fitted withtwo 'fixed lugs d and a movable lug E the stem of which (shown in dottedlines) is slidable lengthwise of the pan D. This lug is under control ofthe screw e which works through the bridgepiece e fixed below the pan.

Fis the, lower mold clamped to the pan D by the lugs d and E.

The upper pan G is provided with two fixed lugs g and two pinchingscrews H which work through brackets h riveted to the pan or formedintegral withit. This pan G is carried on a slotted bar J to which it issecured; by the thumb nut j. The bar J is formed with a spherical head Kon its rear end; this head fits into a hemispherical cup L on the wingM, said wing being secured in the jaws N of the back plate A by a freepin n. A hemispherical cap Ois provided to take against t e upper sideof the head K and this cap is acted upon by the hollow cover nut Pwhichis provided with a knurled flange and a key stem. The depth adjuster bywhich the molds are prevented from being brought too closely together,consists of a chamfered head bolt S which is set in the slot Q. in theback plate A by a thumb'nut g. The heel R of the wing M takes againstthe edge of the head of this bolt.

The mode of using the articulator is as follows :Impressions are takenof the upper and lower jaw of the patient by pressing warmed wax or likeplastic substance into the same, and these impressions are used as moldsin which plaster casts are made. The

bite is obtained by closing the patients jaws on a piece of like plasticmaterial. The two casts are now set in proper register by placing thebite gage so formed between them, and while they are held together inregister they are clamped in the articulator pans by means of the screwsH H and e e. The position of the casts relatively to the articulationpoint a is set by sliding the rods C telescopically through the tubes Band by moving the upper pan G along the slotted bar J, the parts beingfinally secured by means of the set pins Z) and j. It may be necessaryto readjust either or both of the casts after the jaw length adjustmenthas been made as described, in order that the bite will be preciselycorrect. 'lransverse adjustment is effected by means-of the ball and cupjoint which is set after adjustment by screwing down the cap P. The boltS is now moved in the slot Q until it takes against the rear face R ofthe hinge wing M, and it' is then set by means of the nut q. The castsmay now be moved apart about the pin a and the bite gage removed; whenthey are brought into juxtaposition, the register will be correct anddentures fitted therewith will therefore correctly fit the mouth of thepatient. The'plaster molds 'm'ay be removed by retiring the screws H Hback R of said hinge leaf, a ball joint and I clamp, a slotted bar moldcarrier J, a mold pan G, a screw 7' for securing the said pan G on thecarrier J, and mold clamping device on the pan G.

3. In a dental articulator, the combination of a back plate, a lowermold pan mounted telescopically on the lower part of said back plate,screw clamps for securing the mold to said pan, an upper pan similarlyfitted with mold screw clamps, an arm carrying said upper mold pan, apinching screw for securing said upper pan to said arm, and a ball-jointprovided with a tightening screw connecting said arm with a hinge leafarticulated to the upper "part of the back plate. a

I 4. In a dental articulator, the combination with a lower mold pan, ofan'upper mold pan and ,an arm for supporting it, a ball-101m at the endof said arm, and ad- Justable fastening means operatively associatedwith said upper pan and said arm for permitting sliding" and rotationalmovesaid ball-joint forming articulation to the back plates, and anadjustable stop slidable in a slot in the back plate taking against therear side of said leaf.

In testimony whereof I ha ve affixed my signature in presence of twowitnesses.

PATRICK AL RED KENNEDY. Witnesses W. I. DAVIS, M. J. OANDRICK.

